The Stones Project: Subsea, Umbilical, Riser and Flowline Systems

摘要

The Stones project is located in the Walker Ridge (WR) area approximately 200 miles due south of NewrnOrleans in 9,500 feet of water. The host facility is a Floating Production Storage and Offloading (FPSO)rnvessel with a disconnectable buoy that allows the FPSO to move off site in a hurricane event. Subsea wellsrnare located in daisy chained drill centers that tie back to the FPSO via dual Steel Lazy Wave Risers andrnsubsea flowlines. Other key subsea infrastructure includes two production manifolds, eight subsea trees,rnumbilicals and an artificial lift system. Produced gas is exported through a lateral pipeline which ties intornthe Walker Ridge Gathering System located in WR 457.rnThis paper provides an overview of the subsea and flowline system, overall flow assurance strategy, arndescription of the gas export pipeline, and challenges encountered during execution of the project.rnKey challenges include the water depth at the site, furrowed seabed, metocean conditions, slope stabilityrnalong the Sigsbee escarpment, the disconnectable buoy, flow assurance and changes mid execution due torndeep and difficult wells.